(a)
(b)
(c)
Figure 4: (a) Raman spectra of SWNTs grown on Co/MgO at 900°C and 1000°C. (b) Raman spectrum of SWNTs grown on Co/MgO at 650°C and under laser irradiation at 350°C. (c) Raman spectrum of SWNTs grown under laser irradiation after 2 min growth at 850°C (top); Raman spectrum of SWNTs grown under normal CVD (bottom).